<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    * {
        background: #527318;
    }

    input {
        margin: auto 100px 40px auto;
        cursor: pointer;
        width: 100px;
        height: 100px;
    }

    input::after {
        content: '已经勾选';
        display: none;
        width: 150px;
        height: 50px;
        margin-left: 110px;
        margin-top: 40px;
    }

    input:checked::after {
        display: block;
    }
</style>

<body>
    <input type="checkbox">
    <input type="checkbox">
    <input type="checkbox">
</body>

</html>